A simple method for site-directed mutagenesis using the polymerase chain reaction.
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A simple method for site-directed mutagenesis using the polymerase chain reaction.
We have developed a general and simple method for directing specific sequence modifications in a plasmid using the amplification approved by the reaction of the polymerase chain (PCR). The method is based on the amplification of the plasmid assembly using primers that include the desired changes. The method is fast, simple in its execution and requires only minor amounts of plasmid model DNA. It is important that there is no particular requirement for the restriction sites appropriately placed in the sequence to handle.
In our system, the transformant yield was high and the fraction of them hosting plasmids with only the desired change was always about 80%. The generality of the method should make it useful for the direct modification of most cloned genes. The only limitation can be the total length of the plasmid to handle. During the study, we found that the TAQ DNA polymerase used for PCR adds on a single additional base (generally a) at the end of a significant fraction of the newly synthesized channels. These were to be eliminated by the Klenow fragment of the DNA polymerase to ensure the restoration of the genes sequence.
The very thermostable Thermos Aquaticus (TAQ) polymerase DNA is ideal for manual and automated DNA sequencing because it is fast, highly suitable, has little or no exonuclease activity 3′-exonuclease, and is active. On a wide range of temperatures. Sequencing protocols are presented that produce readable extension products greater than 1000 bases with uniform band intensities. A combination of high reaction temperatures and 7-deep-2′-deoxyguanosine analog base was used to sequence G +-rich DNA and to resolve gel compressions. We have modified the reaction conditions of the polymerase chain (PCR) for direct sequencing of the asymmetric PCR products DNA without intermediate purification using the TAQ DNA polymerase. The coupling of the asymmetric PCR model preparation and direct sequencing should facilitate the automation of large-scale sequencing projects.
Long PCR improves the amplification of the Wolbachia DNA: WSP sequences present in 76% of sixty-three arthropod species.
Bacteria belonging to the genus Wolbachia are associated with a variety of breeding anomalies in arthropods. Reaction of the polymerase chain specific to the allele (= standard PCR) has routinely used to amplify Wolbachia DNA from arthropods. While testing the two spider spider spider of tetranychus urticae and other known arthropods to be infected with Wolbachia, the standard PCR frequently produces false negatives, perhaps because the DNA of the host arthropod interferes with an amplification by the Taq DNA polymerase. Long PCR, which uses two enzymes (Taq and PWO), wolbachia DNA systematically amplified and a sensitivity analysis indicated that long PCR was about six orders of more sensitive size than the standard PCR in the rocky amplifier plasmid DNA in Genomic DNA of insects.
An investigation indicated that 76% of the sixty-two arthropod species and two subspecies in thirteen orders have been tested positive for the Wolbachia WSP sequence by long PCR, which is considerably greater than the speed of 16.9% obtained previously for the FTSZ Sequence Using Standard PCR (Werren, JH, Windsor, D. and Gao, L. (1995a) Proc Roc Lond B 262: 197-204). A sub-sample of Long PCR products of fourteen arthropod species and two subspecies were sequenced, both directly and after cloning. Two strains A and eleven b-wolbachia were detected and their WSP sequences show a 23.7% divergence of 23.7% to this locus.
A simple method for site-directed mutagenesis using the polymerase chain reaction.
An evaluation of the polymorphism of the length of the terminal-restriction fragments (T-RLFLP) for studying the structure and dynamics of the microbial community.
A systematic assessment of the value and potential of the polymorphism of the length of the terminal-restriction restriction fragment (T-RLFLP) for the study of the microbial community structure was undertaken. The reproducibility and robustness of the method have been evaluated using isolated environmental DNA samples directly from PCB polluted soil, and as a result of the subsequent polymerase chain reaction (PCR). ADR amplification of the Community Community.
An initial survey for evaluating variability in both polyacrylamide gel electrophoresis circuits showed that almost identical community profiles have been constantly produced from the same sample. Similarly, very little variability has been observed as a result of the variation between replication restriction digestions, PCR amplifications or between replicated DNA insulations. The descending concentrations of the model DNA produce a decrease in the complexity and intensity of the fragments present in the profile of the Community, without any additional fragment detected in the higher dilutions that were not already present when more of Original model DNA has been used. Reducing the number of cycles of PCR has produced similar results. The greater variation between the profiles generated from the same DNA sample has been produced using different polymerases of the Taq DNA, while lower variability levels have been found between PCR products that have been produced. using different annealing temperatures.
Description: A polyclonal antibody against Genome polyprotein. Recognizes Genome polyprotein from Human enterovirus 71. This antibody is Unconjugated. Tested in the following application: ELISA
Description: A polyclonal antibody against Genome polyprotein. Recognizes Genome polyprotein from Hepatitis C virus genotype 1a. This antibody is Unconjugated. Tested in the following application: ELISA
Description: A polyclonal antibody against Genome polyprotein. Recognizes Genome polyprotein from Human rhinovirus A serotype 89. This antibody is Unconjugated. Tested in the following application: ELISA
Description: A polyclonal antibody against Genome polyprotein. Recognizes Genome polyprotein from Dengue virus. This antibody is HRP conjugated. Tested in the following application: ELISA
Description: A polyclonal antibody against Genome polyprotein. Recognizes Genome polyprotein from Human enterovirus 71. This antibody is HRP conjugated. Tested in the following application: ELISA
Description: A polyclonal antibody against Genome polyprotein. Recognizes Genome polyprotein from Hepatitis C virus genotype 1a. This antibody is HRP conjugated. Tested in the following application: ELISA
Description: A polyclonal antibody against Genome polyprotein. Recognizes Genome polyprotein from Human rhinovirus A serotype 89. This antibody is HRP conjugated. Tested in the following application: ELISA
Description: A polyclonal antibody against Genome polyprotein. Recognizes Genome polyprotein from Dengue virus. This antibody is FITC conjugated. Tested in the following application: ELISA
Description: A polyclonal antibody against Genome polyprotein. Recognizes Genome polyprotein from Human enterovirus 71. This antibody is FITC conjugated. Tested in the following application: ELISA
Description: A polyclonal antibody against Genome polyprotein. Recognizes Genome polyprotein from Hepatitis C virus genotype 1a. This antibody is FITC conjugated. Tested in the following application: ELISA
Description: A polyclonal antibody against Genome polyprotein. Recognizes Genome polyprotein from Human rhinovirus A serotype 89. This antibody is FITC conjugated. Tested in the following application: ELISA
Description: A polyclonal antibody against Genome polyprotein. Recognizes Genome polyprotein from Dengue virus. This antibody is Biotin conjugated. Tested in the following application: ELISA
Description: A polyclonal antibody against Genome polyprotein. Recognizes Genome polyprotein from Human enterovirus 71. This antibody is Biotin conjugated. Tested in the following application: ELISA
Description: A polyclonal antibody against Genome polyprotein. Recognizes Genome polyprotein from Hepatitis C virus genotype 1a. This antibody is Biotin conjugated. Tested in the following application: ELISA
Description: A polyclonal antibody against Genome polyprotein. Recognizes Genome polyprotein from Human rhinovirus A serotype 89. This antibody is Biotin conjugated. Tested in the following application: ELISA
Incomplete digestion by the restriction enzyme may, as a result of the generation of partially digested fragments, lead to overestimation of general diversity within a community. The results obtained indicate that, once standardized, a T-RLFLP analysis is a highly reproducible and robust technique that gives high quality fingerprints made up of fragments of precise sizes, which, in principle, could be awarded phylogepedically, a once an appropriate database is constructed.
